It is known to use a circular needling machine for fabricating annular textile structures that are to constitute the fiber reinforcement of annular parts made of composite material, in particular brake disks, such as disks made of carbon/carbon (C/C) material for airplane brakes.
A circular needling machine generally comprises a needling table having a horizontal top surface onto which a helical fiber sheet for needling is applied. Rollers serve to drive the fiber sheet in rotation about a vertical axis by means of friction. The sheet as put into rotation in this way passes under a needling head that overlies an angular sector of the top surface of the needling table. The needling head is moved with vertical reciprocating motion and carries needles that take fibers from within the stacked layers of the fiber sheet in order to transfer them through the layers and thereby bond together the various layers of the fiber sheet. Reference may be made to Document WO 02/088449, which describes an embodiment of such a needling machine.
That type of needling machine presents a device for driving the fiber sheet by means of friction using conical rollers that are arranged above the needling table. Unfortunately, that type of drive presents a certain number of drawbacks. In particular, it makes it necessary to have recourse to a guide at the outside diameter of the sheet so as to keep the sheet around its axis of rotation while it is being moved. In addition, the guide and the rollers impart stresses to the fiber sheet. Finally, since drive is transmitted by friction, the angular position of the sheet of the needling table is uncertain.